Periventricular low intensities on fluid attenuated inversion recovery imaging in the newborn infant: Relationships to the clinical data and long-term outcome

BACKGROUND: The author's previous study showed that it is possible to predict the severity of white matter injury in early infancy by using fluid attenuated inversion recovery (FLAIR) imaging. A follow-up study was performed in order to assess the correlation between the incidence of periventricular low intensities on FLAIR imaging (F-PVLI) and the clinical data including the physiological variables at birth and the long-term outcome of the infant. METHODS: The authors reviewed MRI of 328 newborn infants, which were obtained before 2 months corrected age. Abnormal findings in the periventricular white matter and other part of the brain were recorded. Periventricular abnormal intensities were sorted into four groups according to the FLAIR grade, which comprised normal, F-PVLI 1 (focal), F-PVLI 2 (extensive), cystic periventricular leukomalacia (C-PVL), and diffused leukomalacia. RESULTS: Significantly more periventricular abnormal intensities were detected by FLAIR imaging than by conventional T1 and T2 weighted imaging. In the groups of F-PVLI 2 and C-PVL, the birth weight (BW), gestational age (GA), blood pH and base excess at birth were significantly lower than in the normal group. However, when the study population was defined into very low birth weight infants, F-PVLI 2 had significantly larger BW and GA than normal. The FLAIR grade had a strong correlation with the developmental outcome at 12 and 36 months corrected age. CONCLUSIONS: F-PVLI is a silent but very important white matter injury, which has many features in common with C-PVL. FLAIR imaging could be a strong tool in screening newborn infants at high risk of neurological impairment.     

Neonatal MRI in preterm infants with periventricular leukomalacia and mild disability

Background: The aim of the present study was to describe the neonatal magnetic resonance imaging (MRI) findings of preterm infants with periventricular leukomalacia and mild neurological disability. Methods: MRI findings at term equivalent were retrospectively investigated in eight preterm infants with mild disability and periventricular leukomalacia diagnosed on MRI in infancy. Results: Linear, spotted, or macular areas of hyperintensity on T1‐weighted imaging and hypointensity on T2‐weighted imaging were identified in all subjects in the white matter lateral to the body of the lateral ventricle. No cystic lesions were seen. These findings were more widespread and more clearly visualized on T2‐weighted imaging than T1‐weighted imaging. Conclusions: Linear, spotted, or macular lesions that are hyperintense on T1‐weighted imaging and hypointense on T2‐weighted imaging are possibly compatible with periventricular leukomalacia.     

磁敏感加权成像在早产儿伴脑室旁白质损伤中的应用研究

目的脑室旁白质损伤是早产儿围生期窒息后常见的脑损伤类型之一,其MRI表现具有特征性,但常规序列难以区分病灶内是否合并出血,而出血与否可能影响治疗和预后。该研究应用磁敏感加权成像(SWAN)来检测存在白质损伤的早产儿脑内的出血性病变。方法对临床怀疑围生期窒息后脑损伤的75例早产儿行头颅GE HDx Twin Speed 3.0T MRI检查,扫描序列包括T1FLAIR、T2FLAIR、DWI和SWAN。结果44例(58.7%)早产儿存在脑室旁白质损伤,其中4例(9.1%)存在出血性白质损伤。在这4例中有3例合并生发基质出血-脑室内出血;4例合并小脑出血;1例合并蛛网膜下隙出血。结论脑室旁白质损伤中绝大多数为非出血性损伤,当伴有生发基质出血或脑室内出血时,脑室周围白质损伤病灶中常存在出血。     

Correlation between neuroimaging and neurological outcome in periventricular leukomalacia: Diagnostic criteria

BACKGROUND: Periventricular leukomalacia (PVL) is the most important factor in cerebral palsy in preterm infants. METHODS: In the present study, we investigated 747 preterm infants of less than 36 weeks gestation who were repeatedly examined by cranial ultrasonography and computed tomography (CT) scanning at around 40 weeks of corrected post-menstrual age. The clinical course of these infants was followed for more than 3 years and they were examined by magnetic resonance imaging (MRI) between 12 and 18 months of age. RESULTS: Single examinations in early infancy were not sufficient to diagnose PVL, but the combination of ultrasonography, CT and MRI examinations allowed the clinical diagnosis of PVL. In preterm infants, clinical PVL could be predicted from cystic PVL and periventricular echogenicity (PVE) 3 or PVE 2 prolonged over 3 weeks on ultrasonography and confirmed by MRI after 11 months of corrected age. CONCLUSIONS: We tried to determine diagnostic criteria for PVL by neuroimaging. Such criteria from neuroimaging for PVL may be useful for determining the exact occurrence rate of and clinical risk factors for PVL.     

晚期早产儿脑白质损伤临床特点及磁共振影像学发现

目的：探讨晚期早产儿脑白质损伤的临床特点及常规磁共振成像（MRI）和弥散加权成像（DWI）影像学特征。方法：总结2005年1月至2008年5月中国医科大学盛京医院收治的519例早产儿资料（277例晚期早产儿,242例早期早产儿）,对其头部常规MRI和DWI特征进行分析。结果：晚期早产儿中,脑白质损伤118例,占脑损伤的71.9%（118/164）,占全部晚期早产儿的42.6%（118/277）。早期早产儿脑白质损伤占脑损伤的69.2%（92/133）,占全部早期早产儿的38.0%（92/242）,晚期早产儿脑白质损伤发生率与早期早产儿相比无明显差异。晚期早产儿脑白质损伤中无明显临床症状者占61.9%（73/118）,重症脑损伤（广泛性及弥漫性脑损伤）早期有明显临床症状者占75%（15/20）。损伤1周内,DWI表现为高信号,T1WI信号正常或稍高信号,伴或不伴T2WI高信号;弥漫性损伤者呈DWI高信号,常规MRI无明显信号改变。结论：脑白质损伤在晚期早产儿亦较常见。重症脑白质损伤患儿早期多有明显的临床表现。DWI在损伤早期的敏感度高于常规MRI。［中国当代儿科杂志,2010,12（5）：321-326］     

Limitations of ultrasonography for diagnosing white matter damage in preterm infants

OBJECTIVES: To compare the accuracy of ultrasonography (US) and magnetic resonance imaging (MRI) in diagnosing white matter abnormalities in preterm infants and to determine the specific indications for MRI. DESIGN: Prospective cohort study. SETTING: A neonatal intensive care unit in France. PATIENTS: All preterm infants (相似文献   

弥散加权成像早期预测新生儿缺氧缺血性脑损伤区域及其表观弥散系数值改变

目的 阐明弥散加权成像(diffusion weighted imaging,DWI)可于生后早期预测HIE患儿的损伤区域,并且评估不同区域的ADC值变化情况.方法 研究对象为2006年7月至2009年7月,我院新生儿病房收治26例HIE患儿,其临床分度为重度19例和中度7例,均于生后72 h内完成常规MRI和DWI扫描.其中,10例重度HIE患儿(ADC值组)行8个感兴趣区的ADC值测量,以同期住院的12例无神经系统疾病的足月儿为对照.8个感兴趣区分别为内囊后肢(PLIC)、腹外侧丘脑、基底节、中央沟周围皮层、枕叶皮层、半卵圆中心、脑干、额叶白质.结果 生后72 h内,26例HIE患儿的常规MRI示5例蛛网膜下腔出血、2例硬膜下出血,仅1例患儿的T2WI可见部分皮层稍高信号,此外未见其他异常.但26例HIE患儿的DWI均可见异常高信号.在19例重度HIE患儿中,17例(89%)表现为双侧腹外侧丘脑和中央沟周围皮层的异常高信号(其中6例伴有双侧基底节区异常高信号),仅2例(11%)表现为皮层及皮层下白质的异常高信号.7例中度HIE中,4例表现为皮层及皮层下自质的异常高信号,2例表现为脑室周围白质的异常高信号,仅1例表现为双侧腹外侧丘脑和中央沟周围皮层的异常高信号.ADC值组内囊后肢(PLIC)、腹外侧丘脑、基底节、中央沟周围皮层、枕叶皮层、半卵圆中心、脑干、额叶白质的平均ADC值依次为0.68(0.56～0.88),0.73±0.13,0.67±0.11,0.78±0.22,0.90±0.16,0.87±0.21,0.73±0.19,1.32±0.22×10-3 mm2/S.对照组内囊后肢(PLIC)、腹外侧丘脑、基底节、中央沟周围皮层、枕叶皮层、半卵圆中心、脑干、额叶白质的平均ADC值依次为0.96(0.95～1.02),1.02±0.90,1.15±0.99,1.08±0.07,1.09±0.08,1.39±0.20,0.96±0.05,1.58±0.18×10-3 mm2/S.与对照组相比,ADC值组8个感兴趣区的平均表观弥散系数(apparent difusion coefficient,ADC)值明显降低(P＜0.01).结论 在生后早期,重度HIE患儿的损伤区域大部分为丘脑-中央沟周围皮层,仅少数为皮层及皮层下白质.中度HIE患儿的损伤区域较多样,依次为皮层及皮层下白质、脑室周围白质和丘脑-中央沟周围皮层.HIE患儿的DWI图像异常部位及未见异常部位的ADC值均有不同程度的下降.

Abstract：

Objective To elucidate that diffusion weighted imaging (DWI) can be used to predict the injured regions of neonatal brain with hypoxic-ischemic encephalopathy (HIE) in the early phase of injury, and to measure the apparent diffusion coefficient (ADC) values in the multiple regions of the brain.Method The participants in this study were twenty-six infants with HIE from neonatology ward hospitalized between July 2006 and July 2009.Nineteen patients had severe HIE, and seven had moderate HIE.DWI and conventional magnetic resonance imaging (MRI) were performed for each case within the first 72 hrs.The ADC values of eight regions of interest (ROIs) were measured in ten cases with severe HIE ( ADC values group). ROIs included posterior limb of internal capsule (PLIC), ventrolateral thalami, basal ganglia, perirolandic cortex, occipital cortex, centrum semiovale, brainstem, and frontal white matter.Twelve neonates were enrolled as the control subjects.Results During the first 72 hfs, the conventional MR1 of 26 patients showed subarachnoid hemorrhage in 5, subdural hemorrhage in 2, and mild high signal intensity in the cortex of only one patient.In the 19 cases with severe HIE, abnormal signal intensities were seen in ventrolateral thalami and perirolandie cortex of 17 patients ( 89% ), and the remaining 2 infants showed abnormal cortex and subcortical white matter.In 7 cases with moderate HIE, 4 had abnormal signal intensity in the cortex and subcortical white matter, 2 had abnormal periventricular white matter, and only one showed abnormal signal intensity in the ventrolateral thalami and perirolandic cortex.In the ADC values group, the average ADC values of posterior limb of internal capsule ( PLIC ), ventrolateral thalami, basal ganglia, perirolandic cortex, occipital cortex, centrum semiovale, brainstem, and frontal white matterrespectively were 0.68(0.56-0.88) ,0.73 ±0.13,0.67 ±0.11,0.78 ±0.22,0.90 ±0.16,0.87 ±0.21,0.73 ±0.19,1.32 ±0.22 × 10-3 mm2/S.In the control group, the average ADC values of posterior limb of internal capsule ( PLIC ), ventrolateral thalami, basal ganglia, perirolandic cortex, occipital cortex, centrum semiovale, brainstem, and frontal white matter respectively were 0.96(0.95-1.02), 1.02 ±0.90,1.15 ±0.99,1.08 ±0.07,1.09 ±0.08,1.39 ±0.20,0.96 ±0.05,1.58 ±0.18 × 10 -3 mm2/S. There was statistically significant difference in the average ADC values between each of 8 ROIs of infants with HIE and healthy neonates( P ＜ 0.01 ).Conclusion In the first days after birth, the major injured regions of severe HIE were ventrolateral thalami and perirolandic cortex, the minor injured regions were cortex and subcortical white matter.Multiple regions of moderate HIE were injured, including cortex with subcortical white matter,periventricular white matter, and ventrolateral thalami with perirolandic cortex. The ADC values of the regions with abnormal signal intensity decreased, also some regions with the normal signal intensity.     

Impact of cerebral palsy in patients discharged from neonatal intensive care units

AIM: The aim of this study was to assess the impact and the peculiarities of cerebral palsy (CP) in children discharged from our neonatal intensive care unit (NICU) from January 1998 to April 2004. METHODS: A total of 2 303 children were discharged from our NICU during this period and 1 912 were followed up for 1 year through neurological examination (traditional, Brazelton, general movements) and cranial ultrasound (US); high-risk newborns were evaluated with brain magnetic resonance imaging (MRI) too. RESULTS: In 65 children (3.4% of the follow-up group) were diagnosed CP, and classified as follows: 21 (32%) diplegia, 19 (29%) quadriplegia, 20 (31%) hemiplegia, 4 (6%) double hemiplegia, 1 (2%) dyskinetic form. In diplegia and quadriplegia prevailed low birth weight infants (less than or equal to 2,500 g) and preterm infants, while in hemiplegia prevailed normal birthweight infants (greater than 2,500 g) and infants at term. The main MRI findings were: in diplegia 82% periventricular white matter lesions; in quadriplegia 94% periventricular and/or subcortical white matter lesions; in hemiplegia 95% bilateral periventricular or subcortical white matter lesions, predominating on contralateral cerebral hemisphere; in double hemiplegia 100% periventricular and/or subcortical white matter lesions, 100% enlargement of subarachnoid spaces; in dyskinetic form 100% basal ganglia lesions. CONCLUSIONS: The impact of CP in children discharged from our NICU, in agreement with the literature, is higher than in the total population of newborns, thus it is very important to evaluate carefully high-risk newborns during hospitalization and follow-up, through neurological examination and radiologic imaging (US, MRI), for an accurate and early treatment.     

Hypoxic-ischaemic encephalopathy: early and late magnetic resonance imaging findings in relation to outcome.

Sixteen infants with hypoxic-ischaemic encephalopathy (HIE) were studied using serial magnetic resonance imaging (MRI) up to the age of 2 years. The infants had regular neurological and developmental assessments. An nuclear magnetic resonance (NMR) score was devised to quantify the early and late MRI findings and a neurological optimality score was used to quantify abnormal neurological signs at the time of the final examination. The follow up MRI score was compared with the neonatal MRI score and the outcome of the child. There was a strong positive correlation between the neonatal and follow up MRI scores and between MRI scores and optimality score. All infants with a normal outcome had patchy white matter abnormalities. All infants with an abnormal outcome had extensive white matter abnormalities. The outcome was most severe in those infants with additional basal ganglia atrophy with or without cyst formation. Infants with mild HIE who are developmentally normal at the age of 2 years do not have normal MRI scans and may be at risk of minor neurological problems by school age. Bilateral basal ganglia abnormalities are associated with severe developmental delay, but infants with mainly white matter and cortical abnormalities have less severe problems despite extensive tissue loss.     

MRI和DTI评价早产儿脑白质髓鞘发育

目的 应用磁共振(MRI)、磁共振弥散张量成像(DTI)研究早产儿脑白质髓鞘发育的特点。方法 胎龄≤32周、出生体重<1 500 g的31例早产儿根据头部MRI检查分为早产脑损伤组(12例)和早产无脑损伤组(19例)。选取24例足月儿作为对照组。均于胎龄或纠正胎龄37~40周之间完成头部MRI及DTI检查。测定3组相同感兴趣区的部分各向异性参数(FA)和表观扩散系数(ADC)。结果 早产脑损伤组内囊后肢FA值小于早产无脑损伤组和足月对照组 (P < 0.05);早产脑损伤组和早产无脑损伤组的额叶白质和豆状核的FA值小于足月对照组 (P < 0.05);3组间枕叶白质的FA值差异无显著性 (P > 0.05)。早产脑损伤组和早产无脑损伤组内囊后肢、豆状核、枕叶白质、额叶白质的ADC值高于足月对照组 (P < 0.05)。结论 早产儿脑损伤容易出现内囊后肢深部脑白质髓鞘化障碍或延迟。早产儿至纠正胎龄足月时,无论有无脑损伤,脑周围白质及灰质成熟度均低于足月儿。     

Periventricular haemorrhagic infarction associated with subependymal germinal matrix haemorrhage in the premature newborn. Report of two cases

Two cases of unilateral subependymal germinal matrix haemorrhage associated with homolateral periventricular haemorrhagic infarction (PVHI) are reported in two premature newborns. This association is rather rare. Indeed, PVHI occurs generally with large intraventricular haemorrhage. Diagnosis is made by brain imaging (ultrasound, MRI) scans and single photon emission computed tomography. PVHI is probably caused by obstruction of periventricular venous drainage by large intraventricular haemorrhage leading to a haemorrhagic venous infarction. From our cases, we conclude that extraventricular haemorrhage leading to a large subependymal haematoma can result in obstruction of periventricular venous drainage, subsequent PVHI and abnormal neuromotor development.     

磁共振弥散加权成像在早产儿脑室周围白质软化早期的预测价值

目的 探讨磁共振弥散加权成像(DWI)早期评价和预测早产儿脑室周围白质软化(PVL)的作用及意义.方法 回顾分析2005年8月至2007年4月,在我院新生儿科住院,且经头部MRI确诊的12例PVL早产儿生后7 d内、2 w和4 w的DWI及常规MRI资料.结果 初次检查(平均生后4.5 d)全部病例DWI均显示双侧脑室周围脑白质对称性、弥漫性高信号,常规MRI基本正常;出生后2周DWI示脑白质内不规则高、低混杂信号,而常规MRI则显示相应部位小片状或点状T1WI高信号,T2WI稍低信号;出生后4W DWI示侧脑室后角、枕部三角区大小不等的囊性低信号,常规MRI显示相应病灶的T1WI低信号,T2WI高信号(即囊性PVL改变);出生后4个月常规MRI示囊腔逐渐变小、消失,脑白质减少、脑室扩大.结论 DWI显示的双侧脑室周围白质对称性弥漫性高信号是PVL的最早期表现;所提供的影像学异常变化与晚期常规MRl所证实PVL发生的高度相关性,表明了DWI可能是早期评价脑白质损伤及预测早产儿PVL发生的重要检测手段.     

儿童脑室周围白质软化磁共振表现与临床的关系

目的 探讨儿章脑室周围白质软化(PVL)MRI表现与临床症状的相关性.方法 选取本科47例PVL患儿.回顾性调查其围生期感染、出生体质量、胎龄及窄息情况;分析其MRI表现,包括脑室周围异常高信号、脑室扩大、皮质损伤、脑白质减少程度和胼胝体发育不良,进行PVL、腩性瘫痪(脑瘫)程度及语占障碍分级及视听觉筛查、智力检测,语言发育明显落后的患儿进行孤独症筛查:≥2岁应用孤独症行为量表(ABC),<2岁应用孤独症儿童评定量表(CARS),有抽搐发作的患儿进行脑电图(EEG)检查.分析PVL分级与胎龄、出牛体质量、围生期感染、窒息、脑瘫及语言障碍程度、视听觉障碍、智力及癫痫的相关性.结果 47例患儿中3例运动发育正常,其中完伞性耳聋2例,孤独症1例,余44例均诊断为脑瘫,其中听力障碍24例,视觉障碍19例,其中1例皮质盲,发育商正常仅1例,并癫痼发作11例,其中West综合征2例.按照白质异常信号的范围.脑室扩大及白质减少程度、胼胝体发育情况及有无皮质损害将PVL分为3级.其中Ⅰ级14例,Ⅱ级21例,Ⅲ级12例.围生期感染可导致PVL分级上升(P=0.011);胎龄、出生体质量、窒息与PVL.分级无明显相关性(P>0.05);随着PVL级别的上升,脑瘫、智力低下程度加重(P=0.019、0.000),视觉障碍增多(P=0.024);脑白质减少程度与语言障碍、智力低下、听觉障碍程度及视觉障碍均有相关性(P=0.000、0.000、0.001、0.000);脑室扩大程度与语言发育障碍、智力低下程度及视觉障碍有明显相关性(P=0.000、0.000、0.000);伴随皮质损害时,听觉障碍程度加重(P=0.000);胼胝体发育不良时,脑瘫、语言障碍、智力低下程度加重(P=0.008、0.001、0.000);癫痼的发生与PVL分级及MRI表现无明显相关.结论 减少围牛期感染町减轻PVL程度;PVL影响患儿的运动、语言、视听觉及智力发育,其MRI表现可反映临床及预后,程度越重,预后越差,合并胼胝体发育不良时预后不良.     

高危晚期早产儿脑病临床特点及磁共振影像学评估

目的了解高危晚期早产儿(LPI)脑病的危险因素、临床特点及磁共振(MRI)影像学变化。方法对2009年1月至2014年12月住院且存在脑损伤高危因素的LPI,进行头颅MRI检查,分析LPI脑病危险因素、临床特点及头颅MRI特征。结果完成MRI检查的LPI共1 007例,影像学符合早产儿脑病患儿313例(31.1%)。LPI脑病中白质损伤占76.7%。LPI脑病的发生与胎龄无相关性,但随着出生体重增加,脑病检出率逐渐增高(P0.05)。Logistic回归分析结果显示:复苏史是早产儿脑病发生的独立危险因素(P0.01)。结论早产儿脑病在高危LPI中亦较常见,特别是脑白质损伤。复苏病史是LPI脑病的独立危险因素,需引起重视。     

高危晚期早产儿脑损伤病因学及其磁共振发现

目的 探讨以弥散加权成像(DWI)结合常规磁共振成像(T1WI-T2WI)诊断的高危晚期早产儿脑损伤的相关危险因素及临床特点,并分析不同时间MRI序列的信号特点及DWI的早期诊断价值。方法 首先对符合纳入标准的649例晚期早产儿的MRI片重新阅片,按照脑损伤评估标准得出诊断,其次收集相关的临床资料,分析不同类型脑损伤的危险因素和临床特点,并对其中271例确诊脑白质损伤（CWMD）的MRI序列进行分析,探讨不同类型CWMD的信号特点、损伤部位及结局。结果 ①晚期早产儿发生脑损伤332例（51.2%）,其中CWMD 271例（41.8%）,以局灶性CWMD为主（62.7％,170例）;颅内出血112例（17.3%）,主要为蛛网膜下腔出血55.4%（62/112）。②非出血性脑损伤的危险因素是男性（OR=1.510,95％CI：1.067～2.136,P=0.020）、阴道分娩（OR=2.367,95％CI：0.251～22.294 ,P=0.000）、早发型败血症（OR=2.194,95％CI：1.159～4.155,P=0.016）及抢救复苏史（OR=3.784,95％CI：1.908～7.506,P=0.000）。出血性脑损伤的危险因素是阴道分娩（OR=7.195,95％CI：4.249～12.184 ,P=0.000）和早发型败血症（OR=2.692,95％CI：1.185～6.117,P=0.018）。低钙血症（OR=2.593,95％CI：1.343～5.005,P=0.005）、晚发型败血症（OR=1.533,95％CI：1.012～2.323,P=0.044）和抽搐（OR=4.006,95％CI：1.790～8.970,P=0.001）是非出血性脑损伤组的主要临床特点。出血性脑损伤组主要表现为高血糖和抽搐。③局灶性CWMD 65.3％仅累及一处损伤,主要集中在侧脑室后脚（53.5%）,有97.1%病灶消失或病灶范围减少;广泛性CWMD 79.2%累及胼胝体和内囊;弥漫性CWMD 50％合并灰质损伤,全部发生软化。④生后2周内,DWI具有较高的敏感性,98.0%表现为高信号,T1WI信号无变化或稍高信号,伴或不伴T2WI低信号。局灶性CWMD DWI高信号持续时间长达3周以上,弥漫性CWMD DWI高信号持续时间2周以内。结论 晚期早产儿仍然容易受产前产时因素影响而发生不同类型的脑损伤。对有高危因素,或早期出现临床表现或电解质紊乱的患儿应选择生后2周内（1周内最佳）进行DWI和常规MRI检查,以早期发现病变。局灶性CWMD预后较好,合并有灰质损伤或弥漫性CWMD预后极差,需要动态随访,并进行早期康复训练。     

磁共振成像对新生儿缺氧缺血性脑病预后的早期评估

目的：了解足月新生儿缺氧缺血性脑病（HIE）的临床特点,探讨头颅磁共振成像对HIE预后的早期评估价值。方法：对近5年收治的348例足月新生儿HIE的临床资料进行回顾性分析,包括病史、临床表现、磁共振检查及随访结果等。结果：足月新生儿HIE占同期收治新生儿总数的8.25%,76.2%患儿由出生时窒息引起,其中轻度窒息占59.2%,重度窒息占40.8%。总的预后不良率为10.1%,其中重度脑病的预后不良率27.3%, 中度为10.0%, 轻度为1.5%。磁共振表现为弥漫性脑实质出血与脑梗死、基底节与内囊损伤、细胞毒性脑水肿时重度、中度、轻度脑病患儿的预后不良率分别是100%, 87.5%, 81.8%。结论：HIE仍是新生儿常见疾病,可导致死亡或遗留伤残;其中轻度窒息所占比例大,应引起重视。磁共振成像对预后具有早期判断价值,当出现弥漫性脑实质出血与脑梗死、基底节与内囊损伤、细胞毒性脑水肿时预后可能不良,尤其当两种或以上异常同时存在时。［中国当代儿科杂志,2007,9（5）：407-410］     

新生儿缺氧缺血性脑病磁共振诊断与损伤类型的分类建议

新生儿缺氧缺血性脑病(HIE)有比较统一的临床诊断与分度标准,但是符合相同诊断标准的窒息所致HIE的临床表现、神经病理损伤类型有很大差异。磁共振成像(MRI)能很好地呈现HIE损伤类型、损伤进程,且与其远期神经发育结局密切相关,但不同MRI检查序列所反映的损伤表现可能不尽相同。弥散加权序列适宜的检查时间为出生后2~4 d,常规序列为出生后的4~8 d。HIE的MRI主要损伤类型有丘脑基底节+内囊后肢损伤、分水岭样损伤累及皮层和皮层下白质、局灶-多灶性微小性白质损伤,以及广泛全脑性损伤。严重的急性产时窒息易导致深部灰质损伤(丘脑基底节),也可累及脑干,锥体束是最易受累的白质纤维束,而反复间断性缺氧缺血以及伴有感染、低血糖等易导致分水岭区和深部白质损伤。但上述损伤类型有时很难明确区分,而是以某一类型为主,并非所有HIE都有特征性的MRI表现。     

新生儿缺氧缺血性脑病磁共振动脉自旋标记成像33例报告

目的 探讨动脉自旋标记(arterial spin labeling,ASL) MR灌注技术在新生儿缺氧缺血性脑病(HIE)诊断中的应用价值.方法 选用7例无窒息病史以及无其他神经系统疾病的足月新生儿作为正常对照组,将33例有窒息缺氧病史,临床诊断为HIE的足月新生儿按照临床诊断标准分为轻度组(19例)、中度组(6例)和重度组(8例).正常对照组及HIE病例组均行常规横断位MRI(T1FLAIR、T2WI、T2FLAIR)、1 HMRS及ASL(FAIR序列)扫描.经ADW 4.3工作站Functool软件处理后,观察ASL灌注图像,并对病例组和正常对照组的感兴趣区(双侧灰质、白质、基底节区)进行信号强度值定量测量,求其平均值并进行组间比较.结果 正常对照组及病例组均获得了良好的ASL灌注图像.正常对照组灰质、白质及基底节区平均信号强度分别为125.34±11.76、73.42±11.67和173.65±15.49,差异有统计学意义(P＜0.05).HIE病例组灰质、白质及基底节区平均信号强度值为153.47±11.72、71.35±10.37和217.13±12.51,灰质及基底节区平均信号强度值与正常对照组差异具有统计学意义(P＜0.05),病例组白质平均信号强度值与对照组(两组信号强度值分别为73.42±11.67和71.35±10.37)差异无统计学意义(P＞0.05).结论 ASL灌注技术能够有效地检测HIE患者脑组织异常灌注情况,有助于判断患者脑损伤的程度,并为临床诊疗提供有力依据.     

Neurologic examination in infants with hypoxic-ischemic encephalopathy at age 9 to 14 months: use of optimality scores and correlation with magnetic resonance imaging findings

OBJECTIVES: To evaluate whether a structured and scorable neurologic examination (The Hammersmith Infant Neurological Examination) correlates with early magnetic resonance imaging findings in a group of infants with hypoxic-ischemic encephalopathy (HIE) and whether the scores of this assessment can predict the locomotor function in these children. STUDY DESIGN: A total of 53 term infants fulfilling the criteria for HIE underwent scanning within 4 weeks from delivery with a 1 Tesla HPQ magnet. The scores from the neurologic examination performed between 9 to 14 months were correlated to the neonatal magnetic resonance imaging findings and to the maximal locomotor function defined at the ages of 2 and 4 years. RESULTS: The scores were always optimal in the infants with normal or minor neonatal magnetic resonance imaging findings. The lowest scores were associated with severe basal ganglia and white matter lesions. All the infants who had a global score between 67 and 78 at 1 year were able to walk independently at 2 years and without restrictions at 4 years. Scores between 40 and 67 were associated with restricted mobility and scores <40 with severely limited self-mobility at 2 and 4 years. CONCLUSIONS: The use of a standardized neurologic optimality scoring system gives additional prognostic information, easily available in the clinic, on the severity of the functional motor outcome in infants with HIE.     

3-硝基丙酸致未成熟鼠脑室周围脑白质软化的神经行为学及磁共振成像变化

目的 通过脑内定位注射3-硝基丙酸(3-NPA)建立新生鼠脑室周围白质软化(PVL)模型,探讨远期神经行为学和磁共振成像(MRI)变化.方法 新生5 d(P5)SD大鼠随机分成实验组(NPA组)与假手术组(PBS组),脑立体定位仪定位于左侧脑室上方胼胝体,分别注入等量3-NPA和PBS,造模后1、2、3、9 d灌注固定取脑,石蜡切片作HE染色;术后不同时间点观察体重、睁眼时间等生长发育情况;P29-30进行神经行为学检测,观察两组大鼠肢体肌力、随意运动、情感行为能力和学习记忆能力;P30行MRI检查.结果 NPA组大鼠术后睁眼时间延迟,体重增加高于PBS组,差异有统计学意义(P<0.05);HE染色显示NPA组大鼠P6、p7、P8 NPA组注射3-NPA侧皮质下及脑室周围白质出现不同程度疏松及液化灶,P14时出现同侧脑室明显扩大,PBS组无明显变化;神经行为学检测实验组鼠肢体肌力、随意运动、情感行为能力和学习能力较假手术组减退,评分差异有统计学意义(P<0.05);P30 MRI检查显示NPA组脑内注射侧脑室周围局部有脑组织软化信号改变.结论 P5大鼠脑内注射3-NPA制作的脑室周围白质软化模型.能真实地模拟在体病理改变,经神经行为学检测与临床症状相符,MRI检查可显示脑白质损伤的解剖形态学变化,作为诊断PVL的方法具有可行性.